All Creatures Great and Small star Samuel West reveals 'sad' cast change in season 5

The All Creatures Great and Small cast welcomed two new additions after characters James Herriot and his wife Helen welcomed their adorable baby Jimmy at the end of season four.

Opening up about working with babies while filming the beloved Channel 5 show, Samuel West, who plays Siegfried Farnon, explained that the two babies who played little Jimmy had to be recast ahead of the upcoming Christmas special.

Speaking to HELLO! and other press ahead of season five, which begins on Thursday 19 September, Samuel shared an insight into working with youngsters on set. "You always work with a pair of babies because if one of them asleep, you're not allowed to wake him up," explained the actor. "If they're both asleep, you shoot something else."

Revealing the reason behind the cast change, Samuel continued: "The only problem is that when we got to the Christmas episode, we'd moved forward in time. So the two babies we really liked weren't big enough, so they had to recast them , which was a bit sad."

© Channel 5/Jay Brooks

Anna Madeley, who plays Mrs Hall, revealed how the dynamic on set changed after welcoming babies into the cast. "The babies have changed everything for us," she said. "We have many a Jimmy and when we thought the animals made us concentrate and get it right first time, the babies really make sure. It's been lovely working with them ."

When we return to Darrowby in season five, its Spring of 1941 and baby Jimmy is keeping the residents of Skeldale House on their toes. While Helen is adjusting to life as a new mum, with the help of Mrs Hall and Siegfried, Carmody is now part of the furniture and James is away at RAF Abingdon.

© Channel 5

The synopsis continues: "With World War II now fully underway, Siegfried is taking up the slack at the surgery, Mrs Hall and Helen are considering their contribution within the community, and Carmody is eager to step up. Siegfried is keen to have everyone back, but Tristan's surprise return won't be quite as straightforward as he hoped."

On where we find Siegfried in the new season, Samuel told us: " Busy is where Siegfried is at the beginning . Both the younger, more experienced vets are away and although he's perfectly happy serving his country by being part of a reserved occupation by keeping the milk flowing and the lamb and the beef healthy, of course, he's sad and sometimes disappointed that the other two are away. Because, apart from anything else, the farmers have lost their workers as well. So everything feels like it's slightly held together with a string."

© Channel 5

As for Mrs Hall, she's " knee-deep in nappies ", according to Anna but is looking for more ways to help with the war effort.

"I think now Mrs. Hall is starting to think what's her contribution to the war? We know from her backstory that she was very active in the First World War with the Wrens," epxlains Anna. "So we meet a wonderful character called Bosworth, played by brilliant Jeremy Swift, who is looking for wardens to do all the closing curtains, turn the light off, all that local work," she continued. "So she decides she wants to give that a go and she, in her mind, is the perfect person to do it, because she knows the local community really well."